Dermatology

A. Basic topics

1. Psoriasis

  • A type of systemic papulosquamous disease
  • Epidemiology
    • 2% of whites, less common in other skin colours
    • 20 – 40 years
      • Family history
    • 50 – 100 years
      • No family history
  • Etiology
    • Polygenic inheritance (HLA)
    • Triggers
      • Streptococci URTI
      • Irritation of skin
      • Staph
      • HIV
      • Mechanical irritation
      • Alcohol
      • Stress
      • Drugs
        • Beta blockers
        • Lithium
        • Interferon
        • Chloroquine
  • Pathophysiology
    • Acanthosis
      • Hyperplasia of stratum spinosum
      • Elongated rete ridged
    • Parakeratosis – nuclei retention
    • Hyperkeratosis
    • Munro microabscesses
    • T-cell secreted cytokines
    • Overexpression of beta-defensin -> no secondary superinfection
  • Clinical features
    • Symptom-free intervals with relapsing
    • Lesions
      • Well-demarcated
      • Salmon-coloured erythematous, silvery scaling plaques
      • Mainly on scalp, back and extensor surfaces
        • Elbow
        • Knees
        • Scalp
        • Gluteal cleft
      • Pruritus
    • Nail involvement
      • Nail pitting (small depressions in nail)
      • Oil drop sign – well-circumscribed yellow-red discoloration
      • Brittle nails
      • Onycholysis – separation of the nail plate
        • Nail separates from the skin below -> becomes grey
    • Psoriatic arthritis
      • 5 – 30% of patients
      • Very debilitating
      • Distal and proximal interphalangeal joints
      • Spine
      • Diagnosis (CASPAR)
        • > 3 of these
        • Psoriasis
        • Psoriatic nail problems
        • Negative rheumatoid factor
        • Dactylitis – sausage finger
        • Radiological signs
      • Treatment
        • NSAIDs
        • DMARDs
  • Other forms
    • Guttate psoriasis
      • Drop-sized lesion
      • In children after strep
    • Inverse psoriasis
      • Skin folds and flexor surfaces
  • Diagnosis (mostly clinical)
    • Auspitz sign – pinpoint bleedings when scales are scraped off
    • Koebner phenomenon – skin damage causes psoriasis to appear there
    • Skin biopsy – rarely needed
      • Parakeratosis
      • Munro microabscesses
      • Acanthosis
  • Differential diagnosis
    • Atopic dermatitis/atopic eczema
      • Poorly demarcated
      • Severe pruritus
      • Exudative, not dry
      • Flexor surfaces
    • Seborrheic dermatitis
      • Greasy-looking yellow scales
      • On face and trunk
  • Treatment
    • Moisturizer
    • Avoid nicotine, alcohol
    • Topical
      • Steroids
        • Triamcinolone
        • Fluocinonide
        • Clobetasol
      • Vitamin D derivatives
        • Calcipotriene
      • Tar preparations
      • Retinoids
    • Systemic
      • MTX
      • Retinoids
      • Cyclosporine
    • Biological therapy
      • Adalimumab, infliximab, etanercept – TNF alpha
      • Secukinumab – IL-17
      • Briakinumab – IL-23
    • Phototherapy
      • UVB therapy
        • Narrow-band UVB
      • PUVA (psoralen + UVA)
        • Psoralen increases photosensitivity of skin
        • UVA radiation
  • Complications
    • Increased CV risk
    • Metabolic syndrome
    • Kidney disease

2. Pyodermas

  • “Free” pyodermas
  • Impetigo
    • Superficial skin infection
    • Highly infectious
    • Children
      • Most common bacterial skin infection in children
    • Etiology
      • Staph aureus – 80%
      • Strep pyogenes
      • Risk factors
        • Diabetes
        • Immunosuppression
      • Secondary – superinfection of atopic dermatitis, etc
    • Clinical features
      • Honey-crusted lesions
        • The result of ruptured pustules
      • Central face
      • Itching
      • Can be bullous
    • Types
      • Ecthyma
        • A form of impetigo that extends into the dermis and ulcerates
        • Risk factors
          • Diabetes
          • Immunosuppression
        • Round superficial ulcers
    • Treatment
      • Antibacterial wash
      • Mild – topical antibiotics
        • Mupirocin
      • Severe – oral antibiotics
        • Amoxicillin
    • Complications
      • Post-streptococcal GN
  • Cellulitis
    • Deeper than impetigo
    • Infection of deep dermis and subcutaneous tissue
    • Etiology
      • Staph aureus -> purulent cellulitis
      • Strep pyogenes -> nonpurulent cellulitis
    • Primary – entry through minor skin injury
    • Secondary – to systemic infection
    • Clinical features
      • Erythematous lesion with poorly defined margins
      • Purulent cellulitis -> purulent exudate
    • Treatment
      • Penicillin
  • Erysipelas
    • Special type of cellulitis caused by strep pyogenes
    • Epidemiology
      • Children
      • Poor circulation
        • Stasis
      • Diabetics
      • Chronic oedema
    • Spreads by superficial lymph vessels
    • Clinical features
      • On lower limbs – 80%
      • On face – rarely
      • Large erythema, irregular borders
      • Tender
      • Rapidly advancing borders
      • Oedema
      • Warm
      • Fever
    • Site of entry needs to be located
      • Ulcers
      • Interdigital lesion
      • Fungal infections
    • Treatment
      • Oral antibiotics
        • Amoxicillin/clavulanic acid
      • Bed rest
      • Icing
      • Compression
      • Elevation
    • Complications
      • Necrotizing fasciitis
      • Sepsis
      • Residual erysipelas
  • Necrotizing fasciitis
    • Necrotizing infection of deep subcutaneous tissue
    • Etiology
      • Strep pyogenes
      • Staph aureus
      • Pseudomonas
    • Clinical features
      • Painful, haemorrhagic, necrotizing lesion
    • High mortality
    • Treatment
      • Surgical removal of affected fascia (necrectomy)
      • Antibiotics
      • Intensive care
  • Follicular pyodermas
    • Folliculitis
      • Any age group
      • Terminal or vellus hairs
      • Usually bacterial
        • Mainly staph aureus
      • Clinical features
        • Tender papule/pustule of hair follicle
      • Treatment
        • Dicloxacillin
        • Incision and drainage for large lesions
    • Furuncle
      • Well-demarcated, firm, painful, purulent nodule
      • Large red base
      • Subcutaneous abscess
    • Carbuncle
      • Coalescence of furuncles
    • Skin abscess
      • Large nodule

3. Basal cell carcinoma and squamous cell carcinoma

  • Basal cell carcinoma
    • Most common skin cancer
    • Related to mutations in the hedgehog pathway
    • Risk factors
      • Chronic sun exposure
      • Old age
      • Skin types I and II
    • Clinical features
      • Pearly papule or nodule
      • Rolled border
      • Central crater of ulceration
      • On sun-exposed skin
        • Usually upper lip/nose area
      • Slow growing
    • Types
      • Nodular BCC
        • Most common type
      • Superficial BCC
        • On trunk
        • Flat plaque lesion
      • Nevoid basal cell carcinoma syndrome
    • Prognosis
      • Virtually never metastasizes
      • Locally aggressive
    • Diagnosis
      • Full-thickness biopsy -> histology
    • Treatment
      • Surgical excision
      • Irradiation
      • Mohs micrographic surgery
      • Hedgehog pathway inhibitors
      • For low-risk, spf BCC
        • Photodynamic therapy
        • Cryotherapy
        • 5-FU
        • Imiquimod cream
    • Follow-up
      • Physical examination at 3, 6, 12 months
      • Sun protection
  • Squamous cell carcinoma
    • Second most common skin cancer
    • Risk factors
      • Chronic sun exposure
      • Precancerous lesions
        • Actinic keratosis
        • Bowen disease (SCC in situ)
        • Leukoplakia
      • Radiation
      • Chronic scars, ulcers
      • Arsenic, tar
    • Clinical features
      • Painless, non-healing, bleeding ulcer or nodule
      • Rapid growing
      • On sun-exposed areas
        • Face and neck
        • Lower lip
    • Prognosis
      • 5% risk of metastasis
    • Diagnosis
      • Punch biopsy
    • Treatment
      • Surgical excision with 5 mm safety border
      • Radiation therapy
      • Mohs micrographic surgery
      • For low-risk, small
        • Cryotherapy
        • Curettage
      • For metastasis
        • Chemotherapy
          • Platina
          • 5-FU
        • EGFR inhibitors – cetuximab
        • PD-1 inhibitor – cemeplimab
    • Follow-up
      • Physical examination
      • Regional ultrasound
      • Chest x-ray
      • Abdominal US
      • Sun protection

4. Atopic dermatitis

  • Affects 10% of children, but only 1 – 3% of adults
  • Associated with other atopic diseases
    • Asthma
    • Allergic rhinitis
  • Etiology
    • Polygenic inheritance
    • Environmental riggers
      • Dust
      • Heat
      • Infection
      • Skin irritation
  • Pathophysiology
    • Epidermal skin barrier defect
      • -> water loss
      • -> allergens can penetrate barrier
    • Abnormal immune response
  • Clinical features
    • Morphology
      • Acute
        • Erythematous maculopapular rash
        • Dry plaques
        • Oedema
      • Chronic
        • Lichenification
        • Scaling
        • Fissures
    • Mostly on flexor surfaces
      • Except in infants
    • Pruritus
    • Dry skin
    • Cheilitis
  • Diagnosis
    • Clinical
    • Serum IgE elevated
    • Serum LDH elevated
  • Complications
    • Staph infection
    • Eczema herpeticum
    • Tinea
  • Treatment
    • Emollients
    • Topical corticosteroids
      • Mometasone
      • Clobetasol
    • Topical calcineurin inhibitors
      • Tacrolimus
    • Oral antihistamines
    • Oral immunosuppressive therapy
      • Corticosteroids
      • Cyclosporine
    • Biological treatment
      • Anti-IL-4 – dupilumab
      • Anti-IL-5 – mepolizumab
      • Anti-IL-31 – prevents itching
      • Anti-TSLP

5. Leg ulcer

  • Leg ulcer
    • Etiology
      • Chronic venous disease
      • Peripheral artery disease
      • Neuropathic ulcer
        • Diabetes
      • Decubitus
      • Trauma
      • Infections
      • Dermatoses (SLE, pyoderma gangrenosum)
      • Neoplastic
    • Morphology
      • Venous ulcer
        • Above the ankle
        • Mild pain
          • Pain improves when raising leg
        • Shallow ulcer
      • Arterial ulcer
        • Punched-out well-defined ulcer
        • Pressure points of the legs (malleolus, toes)
        • Severe pain
          • Pain worsens when raising leg
    • Treatment
      • Underlying disease
      • Surgical
        • Irrigation
        • Debridement
          • Removal of dead, damaged or infected tissue
        • Wet dressing
        • Skin grafting
      • Local therapy
        • Wound healing
        • Compression
      • Treating adjacent skin
  • Peripheral artery disease
    • Staging
      • Fontaine stage I – symptom free
      • Fontaine stage II – Claudication > 50m
      • Fontaine stage III – Claudication < 50m
      • Fontaine stage IV – Necrosis, gangrene
    • Diagnosis
      • Inspection
      • Doppler index
      • Angiography
    • Therapy
      • Conservative
      • Interventional radiology
      • Vascular surgery
  • Lymphoedema
    • Treatment
      • Conservative (Compression)
      • Vascular surgery
  • Chronic venous diseases
    • Older females
    • Risk factors
      • Female
      • Previous thrombus
      • Pregnancy
      • Standing for long periods
      • Oral contraceptives
    • Varicose veins
      • Dilated torturous superficial veins with knots
    • Chronic venous insufficiency
      • Increased venous pressure -> oedema -> tissue ischaemia
    • Clinical features
      • Local oedema
      • Red-brown pigmentation (haemosiderosis)
      • Loss of hair
      • Smooth skin
      • Stasis dermatitis
    • CEAP classification
      • Clinical
      • Etiology
      • Anatomy
      • Pathophysiology
    • Diagnosis
      • Doppler ultrasound
    • Treatment
      • Conservative
        • Compression
        • Elevation of legs
        • Lymphatic drainage massage
      • Vein ablation
        • Thermal ablation
        • Chemical ablation (sclerotherapy)

6. Skin diseases caused by human papilloma virus (HPV)

  • Warts (verruca)
    • Histology
      • Hyperkeratosis (hyperplasia of str. corneum)
      • Acanthosis (hyperplasia of epidermis)
      • Papillomatosis
    • Hard papules/plaques
    • Risk factors
      • Immunosuppression
    • Due to HPV
    • Verruca vulgaris (common wart)
      • HPV 1, 2, 4, 7
      • Most common in kids
      • On elbows, knees, fingers, palms
      • Skin-coloured or whitish, rough, scaly papules
      • Cauliflower-appearance
    • Verruca plana (flat warts)
      • HPV 3, 11
      • On face, back of hand, legs
      • Skin-coloured, smooth papules, flat surface
    • Verruca plantaris (plantar warts)
      • HPV 1, 2, 4
      • Soles of the feet
      • Skin-coloured
      • Rough surface
    • Treatment
      • Usually resolves by themselves (can take years)
      • Topical treatment
        • Keratolytics
          • Salicylic acid
        • Retinoic acid
        • Cytostatic
          • Podophyllin
          • 5-FU cream
        • Immune therapy
          • Imiquimod
      • Surgery
        • Cryotherapy
        • Surgical excision
          • Leaves permanent, painful scars
      • Prevention
        • Vaccination
          • Cervarix – 16, 18
          • Silgard – 6, 11, 16, 18
          • Gardasil 9 – 6, 11, 16, 18, 31, 33, 45, 52, 58
  • Condyloma acuminata – genital warts
    • HPV 6, 11
    • Exophytic, cauliflower-like lesions
    • In anogenital area or mucous membranes
    • STD
  • Giant condyloma acuminatum
    • HPV 6, 11
    • Exophytic wart-like locally invasive squamous cell carcinoma without tendency to metastasize
  • Precancerous lesions
    • Vulvar intraepithelial neoplasia
    • Vaginal intraepithelial neoplasia
    • Flat condylomata
      • Flat, white-brown plaques in anogenital region
      • High risk of malignancy
  • Anogenital squamous cell carcinoma
    • Vaginal cancer
    • Vulvar cancer
    • Anal cancer
    • Penile cancer

7. Herpes simplex virus (HSV) infections of the skin

  • Herpes viruses
    • α herpes viruses
      • Lie latent in sensory ganglia neurons
      • Replicate quickly
      • Herpes simplex 1
      • Herpes simplex 2
      • Varicella zoster virus
    • β herpes viruses
      • Lie latent in leukocytes
      • Human herpes virus 6 – roseola infantum/sixth disease
      • Human herpes virus 7
      • CMV
    • γ herpes viruses
      • Lie latent in lymphocytes
      • Human herpes virus 8
      • EBV
      • Are oncogenic
  • HSV infections
    • Labial herpes
      • On lips
      • HSV-1 in 90%
      • HSV-2 in 10%
      • Clinical features
        • Prodromal symptoms – 24 hours before outbreak
          • Pain
          • tingling
          • Burning
        • Recurring, erythematous vesicles that turn into painful ulcerations
      • Complications
        • Herpetic gingivostomatitis
          • In children and immunocompromised
          • Often the primary infection
          • Erythema, painful ulceration on perioral skin and oral mucosa
    • Genital herpes
      • On genital organs
      • HSV-2 in most cases
      • HSV-1 rarely
      • Incubation period – 2 – 7 days
      • Clinical features
        • Many are asymptomatic
        • Painful lymphadenopathy
        • Vesicles that ulcerate
    • Eczema herpeticum
      • HSV-1, HSV-2
      • On pre-existing skin conditions
        • Atopic dermatitis
      • Extensive disseminated and painful eruptions on head and upper body
      • Erythematous skin with multiple, round vesicles
      • It’s an emergency
      • Treatment -> IV acyclovir
    • Herpetic whitlow
      • In children and healthcare workers who come into contact with saliva
      • Direct contact with infected saliva through a break in the skin
      • Pain, burning, oedema in finger
      • Lymphadenopathy
    • Treatment
      • Decreases duration and severity
      • Most effective if initiated within 72 hours
      • Mild disease
        • Oral acyclovir (5 x 800mg for 10 days)
      • Severe disease
        • IV acyclovir
      • Acyclovir-resistance -> foscarnet

8. Skin diseases caused by varicella zoster virus

    • Varicella (chickenpox)
      • Primary infection during childhood
      • Lasts 6 days in immunocompetent persons
      • Transmission
        • Highly contagious
        • Airborne transmission
        • Incubation period 2 weeks
      • Clinical features
        • Lesions covering the entire body
        • Severe pruritus
        • Macules -> papules -> vesicles with erythematous base -> crusts
          • All of these stages are present simultaneously, which is a hallmark for the disease
        • Fever
      • Virus remains latent in sensory ganglia
      • Diagnosis
        • Clinical -> characteristic rash
        • Tzanck smear, PCR
      • Treatment
        • For pruritus
          • Calamine lotion
          • Pramoxine gel
          • Oral antihistamines
        • Therapy
          • Only for severe cases or high-risk groups (adults, immunosuppressed)
          • Acyclovir
          • Post-exposure prophylaxis

Active immunization (vaccine)

Passive immunization (immunoglobulins)

      • Prevention
        • Vaccination
      • Complication
        • Bacterial superinfection
          • Impetigo
          • Phlegmon
        • Scarring
        • Congenital varicella syndrome (if chickenpox during pregnancy)
    • Shingles (herpes zoster)
      • Reactivation
      • Older patients
      • Triggers
        • Immunosuppression
        • Advanced age
        • Malignancy
        • Malnutrition
      • Clinical features
        • Erupts in dermatome pattern
        • Severe pain
        • Erythematous maculopapular rash -> vesicles -> rupture
      • Complications
        • Herpes zoster oticus
          • Herpes in facial and vestibulocochlear nerve
          • Blindness
        • Herpes zoster ophthalmicus
          • Herpes in ophthalmic part of trigeminal nerve
          • Facial paresis
          • SN hearing loss
        • Post-herpetic neuralgia
        • Herpes zoster encephalitis
      • Diagnosis
        • Clinical -> characteristic rash
      • Treatment
        • Wet dressing with aluminium acetate
        • 5 x 800mg acyclovir for 10 days
        • NSAIDs

9. Autoimmune bullous skin diseases

  • Bullous pemphigoid
    • In elderly
    • Benign disease, responds well to treatment
    • Most common autoimmune bullous disease
    • Pathomechanism
      • Autoantibodies against hemidesmosomes
    • Clinical features
      • Prodromal stage
        • Weeks before onset of blistering
        • Urticarial lesions
      • Large, tense, subepidermal bulla
        • Don’t rupture easily
      • Intensely pruritic
      • Lower limbs, axilla
      • Rarely oral involvement
    • Diagnosis
      • Negative Nikolsky
      • Histology and immunofluorescence
    • Treatment
      • Prednisone (0,5 – 1 mg/bwkg)
      • Azathioprine, immunosuppressants
  • Pemphigus vulgaris
    • In middle-aged, elderly
    • Deadly without treatment
    • Pathomechanism
      • Autoantibodies against desmosomes
      • Acantholysis – loss of cell-cell adhesion
    • Clinical features
      • Painful, flaccid, intraepidermal (superficial) blisters
      • -> lesions rupture
      • -> erosions and crusts
      • -> re-epithelialization with hyperpigmentation but no scarring
      • No pruritus
      • Lesions often begin in oral mucosa then to body parts exposed to pressure
    • Diagnosis
      • Positive Nikolsky – Skin comes off with scraping
      • Histology and immunofluorescence
    • Treatment
      • High-dose prednisone (1-2 mg/bwkg)
      • Azathioprine, other immunosuppressants
  • Dermatitis herpetiformis
    • In young adults
    • Risk factors
      • Coeliac disease
      • Iodide sensitivity
      • HLA-DR3
      • HLA-DQ2
    • Pathomechanism
      • Tissue transglutaminase and epidermal transglutaminase antibodies
    • Clinical features
      • Chronic, recurrent
      • Tense, grouped, subepidermal vesicles
        • Herpetiform appearance, hence the name
      • Intensely pruritic
      • Bilateral, symmetrical distribution
        • Elbows, knees
      • No mucosal involvement
    • Diagnosis
      • Coeliac antibodies
      • Histology and immunofluorescence
    • Treatment
      • Dapsone
      • Gluten-free diet
  • Epidermolysis bullosa
    • Group of disorders where subepidermal blisters form following trauma
    • Not autoimmune
    • Epidermolysis bullosa simplex
    • Junctional epidermolysis bullosa
    • Dystrophic epidermolysis bullosa
    • Epidermolysis bullosa acquisita

10. Lupus erythematosus and its variants

  • Systemic lupus erythematosus
    • Clinical features
      • Skin
        • Butterfly rash
          • Nasolabial fold spared
        • Photosensitivity
        • Discoid rash -> atrophic scars
        • Oral ulcers
      • Systemic
        • Arthritis
        • Fever
        • Etc.
    • Treatment
      • Steroids
      • Cyclophosphamide
      • Azathioprine
  • Cutaneous lupus erythematosus
    • Chronic discoid lupus erythematosus (CDLE)
      • Epidemiology
        • Most common cutaneous type
        • African American women
      • Clinical features
        • Erythematous scaling plaques
        • -> leaves atrophic scars
        • Ocular and mucosal lesions
        • Affects face, scalp, neck (sun-exposed areas)
        • No systemic symptoms
    • Subacute cutaneous lupus erythematosus (SCLE)
      • Clinical features
        • Persisting diffuse erythema on face or sun-exposed areas
        • Annular or psoriasiform erythematous plaques
        • Morbilliform rash on trunk
        • Affects neck, shoulders, forearms
      • Diagnosis
        • Anti-Ro antibody
    • Drug-induced lupus erythematosus (DILE)
      • Resolves after discontinuation of the drug
      • In elderly
      • May occur years after starting the drug
      • Etiology
        • Sulpha drugs
          • Thiazides
          • Sulfamethoxazole
          • Sulfasalazine
          • Sulfonylurea
        • Methyldopa
        • Isoniazid
          • Especially slow acetylators
        • Phenytoin
      • Clinical features
        • Rash
        • Myalgia
        • Fever
        • Polyarthritis
        • Serositis
      • Diagnosis
        • Anti-histone antibodies
    • Treatment of cutaneous lupus erythematous
      • Hydroxychloroquine
      • Steroids
      • Immunosuppressants
      • Sunscreen

11. Scleroderma and its variants

  • Scleroderma
  • Abnormal growth of connective tissue
  • In all types the skin is thickened and hardened
  • Classification of scleroderma
    • Systemic sclerosis/systemic scleroderma
      • Limited systemic sclerosis/CREST syndrome
      • Diffuse systemic sclerosis
      • Systemic sclerosis sine scleroderma
    • Localized scleroderma
      • Morphea
      • Linear scleroderma
  • Systemic sclerosis
    • Sclerosis of internal organs in addition to the skin
    • Skin symptoms
      • Thickening and hardening of skin
      • Depigmentation (except perifollicular area)
        • Salt-and-pepper appearance
      • Sclerodactyly
      • Face
        • Loss of expression
        • Shortened frenulum
        • Microstomia
    • Limited systemic sclerosis/CREST syndrome
      • More common
      • Skin manifestations are limited to hands, fingers and face
      • Organ involvement is rare and limited
      • Clinical features
        • Calcinosis cutis – calcium deposits on pressure points of extremities
        • Raynaud’s phenomenon
        • Esophageal hypomobility
        • Sclerodactyly
          • Red-blue discoloration of fingers
          • Fibrosis of fingers
          • Atrophy and necrotic spots
        • Telangiectasia
    • Diffuse systemic sclerosis
      • Less common
      • More aggressive
      • Early organ involvement
      • Clinical features
        • Oesophageal dysmotility
        • Small bowel dysmotility
        • Pulmonary hypertension
        • Interstitial lung disease
        • Cardiac fibrosis
        • Renal disease
  • Localized scleroderma
    • No organ involvement, only skin
    • Only localized parts of the skin are affected
    • Morphea
      • Isolated patches of hardened skin
      • No organ involvement
      • Treatment
        • PUVA
        • Intralesional steroid injection
    • Linear scleroderma
      • Starts as a line of hardened skin
      • Develops in childhood
      • Treatment
        • PUVA

12. Malignant melanoma

  • Epidemiology
    • Only 2% of skin cancer
    • Responsible for most skin cancer-related deaths
    • Higher incidence in sun-rich countries like Australia compared to Europe
    • Average age at onset ~50
  • Risk factors
    • Excessive UV exposure
    • Fitzpatrick skin type I and II
      • Easily burns
      • Almost never suntans
      • Often have freckles
    • Precancerous lesions
      • Dysplastic nevi
      • Dysplastic nevus syndrome – 100% risk of developing melanoma
      • Lentigo maligna
      • Congenital nevi
    • Indoor tanning
    • Sunburns in childhood (>3)
    • Positive family history
    • Immunosuppression
    • Familial genetic mutations
      • BRAF (most common)
      • NRAS
      • p16 family
  • Pathogenesis
    • 2 growth phases:
    • Radial/horizontal growth phase
      • Tumor grows horizontally along epidermis
      • No capacity to metastasize
    • Vertical growth phase
      • Tumor grows vertically into the dermis
      • Can metastasize
  • Subtypes
    • Superficial spreading melanoma
      • 60% of all cases
      • Slow radial growth phase, mostly superficial spreading
    • Nodular melanoma
      • 20% of all cases
      • Reddish-brownish-blackish nodule
      • Can be ulcerated
      • Has no radial growth phase, only vertical
      • Poorer prognosis
    • Lentigo maligna melanoma
      • 10% of cases
      • Originates from lentigo maligna in elderly
      • Slow radial growth phase
      • Lesion is often a large and irregularly shaped patch
    • Acral lentiginous melanoma
      • 5% of cases
      • Slow radial growth phase
      • Occurs on nailbeds, palms and soles of dark-skinned and Asian persons
      • Unrelated to UV exposure
    • Amelanotic melanoma
      • Non-pigmented nodule
  • Clinical features
    • Pruritic, bleeding skin lesion
    • On the back or chest in men
    • On extremities in women
  • Diagnosis
    • ABCDE criteria – distinguishing between benign and malignant lesions
      • Asymmetry
      • Border irregular
      • Colour irregular
      • Diameter enlarged (> 5 mm)
      • Evolution (changes over time)
    • Ugly duckling sign
      • The lesion looks different from other nevi on the same patient
    • Dermoscope
    • Histopathological
      • Gives definitive diagnosis
      • Full-thickness biopsy with 1 – 2 mm safety margin
      • Shows atypical melanocytes and atypical architecture
  • Prognosis
    • Breslow depth – from the top of the stratum granulosum to the deepest invasive cell
    • Presence of ulceration
    • Number of mitoses
    • Clark level
    • The subtype
    • Presence of metastasis
      • Usually metastasizes to liver, lung, brain, bone
      • Can metastasize into unusual locations like the heart and gallbladder
      • Metastases are black
  • Staging
    • TNM
    • T = Based on Breslow depth
      • “a” – if there is no ulceration
      • “b” – if there is ulceration
    • N – lymph node
      • Any melanoma with lymph node involvement is stage III
    • M – metastasis
      • Any melanoma with metastasis is stage IV
  • Treatment
    • Surgical excision with safety margin
      • Melanoma in situ – 0,5 cm safety margin
      • Breslow depth < 1 mm – 1 cm safety margin
      • Breslow depth > 1 mm – 1 – 2 cm safety margin
    • Non-surgical treatment
      • For stage III and stage IV melanoma
      • Immune checkpoint inhibitors
        • Anti-CTLA-4 antibodies
          • Ipilimumab
        • Anti-PD-1 antibodies
          • Nivolumab
          • Pembrolizumab
      • Inhibitors of mutated proteins
        • BRAF inhibitor – dabrafenib
        • MEK inhibitor – trametinib

13. Fungal diseases of the skin and its appendages

  • Diagnosis of fungal infections
    • KOH preparation -> hyphae/yeasts visible under microscope
      • KOH dissolves keratin
    • Culture
    • Wood-light – green fluorescence UV lamp
  • Treatment of fungal infections
    • Terbinafine – for dermatophytoses
    • Fluconasol – for candida
    • Itraconazole – for candida, dermatophytoses
    • Ketoconazole – for Malassezia (pityrasis versicolor)
  • Epidermomycoses
    • By dermatophytes
    • Risk factors
      • Children
      • Immunocompromised
      • Diabetes
    • Clinical features
      • Pruritus
      • Scaling
      • Erythema
    • Treatment
      • Topical antifungals
        • Terbinafine
        • Azoles
      • Oral antifungals
        • For immunocompromised persons
        • Terbinafine
        • Itraconazole
    • Tinea facialis – face
    • Tinea corporis – body
    • Tinea cruris – inguinal area
    • Tinea manuum – hands
      • Usually affects two feet and one hand (syndrome)
      • Because the person scratches the feet with the dominant hand
    • Tinea pedis – feet
  • Onychomycoses
    • Discoloured and brittle nails
    • Candida
    • Tinea unguium
    • Treatment
      • Terbinafine
      • Itraconazole
  • Trichomycosis
    • Tinea capitis – scalp
      • Dandruff
      • Smooth areas of hair loss
    • Kerion – very inflamed abscess-like mass
    • Favus – yellow crust
  • Candida
    • Albicans most common
    • Risk factors
      • Immunosuppression
      • Diabetes
      • Antibiotic therapy
    • Skin infections
      • Oral candidiasis
      • Angular cheilitis
      • Vulvovaginal candidiasis
      • Balanitis
      • Intertrigo – infection of the skin folds
      • Interdigital candidiasis
      • Diaper rash
      • Chronic mucocutaneous candidiasis
        • Congenital impaired T-cell function
    • Clinical features
      • Pruritic erythematous plaque
      • White layer – on mucous membranes, genital organs
    • Systemic
      • Candida sepsis
        • Fever that doesn’t improve with antibiotics
      • Invasive candidiasis
  • Pityriasis versicolor
    • Risk factors
      • Hot, humid environment
      • Excessive sweat
    • Clinical features
      • Hypomelanotic macules
    • Treatment
      • Topical ketoconazole cream
      • Ketoconazole shampoo
  • Cryptococcosis
    • Immunocompromised patients
    • Cutaneous cryptococcosis
      • Molluscum contagiosum-like papules
    • Can also cause pneumonia and meningitis
    • Cryptococcal meningitis
    • Treatment
      • Fluconazole
      • Amphotericin
      • Flucytosine
  • Aspergillosis
    • Immunocompromised patients
    • Necrotizing nodules
    • Abscess

14. Drug allergy

  • Classification according to timeline
    • Immediate (< 1 hour)
      • Urticaria
      • Angioedema
      • Rhinitis
      • Bronchospasm
      • Anaphylaxis
    • Non-immediate (> 1 hour)
      • Delayed urticaria
      • Maculopapular exanthema
      • Erythroderma
      • Vasculitis
      • Stevens-Johnson syndrome (SJS)
      • Toxic epidermal necrolysis (TEN)
      • Drug reaction with eosinophilia and systemic symptoms (DRESS)
      • Acute generalized exanthematous pustulosis (AGEP)
      • Symmetrical drug-related intertriginous and flexural exanthemas (SDRIFE)
  • Classification according to pathomechanism
    • Type I hypersensitivity
      • IgE-mediated mast cell activation as a reaction to a soluble antigen
      • All immediate drug allergies
      • Treatment
        • Eliminate culprit drug
        • Antihistamines
    • Type III hypersensitivity
      • IgG-mediated complement activation as a reaction to a soluble antigen
      • Vasculitis
      • Serum sickness
    • Type IVa hypersensitivity
      • Cell-mediated macrophage activation as a reaction to a presented antigen
      • Tuberculin reaction
      • Contact dermatitis
    • Type IVb hypersensitivity
      • Cell-mediated eosinophil activation as a reaction to a presented antigen
      • DRESS
      • Maculopapular exanthema
      • Erythroderma
    • Type IVc hypersensitivity
      • Cell-mediated T-cell activation as a reaction to a presented antigen
      • Stevens-Johnsons syndrome
      • Toxic epidermal necrolysis
    • Type IVd hypersensitivity
      • Cell-mediated neutrophils activation as a reaction to a presented antigen
      • AGEP
  • Drug-induced urticaria
    • Drugs
      • Penicillin
      • Aspirin
      • NSAIDs
  • Angioedema/Quincke-oedema
    • Drugs
      • NSAIDs
      • Aspirin
      • ACE-inhibitors (not technically a drug allergy)
    • Clinical features
      • Facial oedema
      • If laryngeal involvement – dyspnoea, inspiratory stridor
    • Treatment
      • Epinephrine
      • Steroids
      • Antihistamines
  • Anaphylaxis
    • Drugs
      • Lidocaine
      • Anaesthetics
      • Aspirin
      • Contrast
      • NSAIDs
    • After minutes – hours
    • Clinical features
      • Hypotension
      • Bronchospasm, laryngeal oedema -> dyspnoea, inspiratory stridor
    • Treatment
      • Epinephrine
      • Steroids
      • Antihistamines
  • Drug-induced vasculitis
    • Drugs
      • Antibiotics
      • Analgesics
    • Clinical features
      • Painful, palpable purpura
      • Urticaria
    • Resolve after drug cessation
  • Serum sickness
    • Drugs
      • NSAIDs
      • Penicillins
    • Clinical features
      • Fever
      • Rash
      • Arthralgia
    • Resolve after drug cessation
  • Maculopapular exanthema
    • On trunk, extremities
    • No eosinophilia
    • No systemic symptoms
    • Resolve after drug cessation
  • Erythroderma
    • Erythema, scaling of the whole body
    • Eosinophilia
    • No systemic symptoms
    • Resolve after drug cessation
  • DRESS syndrome
    • Drug-related eosinophilia and systemic symptoms
      • Also called drug-induced hypersensitivity syndrome
    • Drugs
      • Allopurinol
      • Antiepileptics
      • Antibiotics
    • Risk factors
      • Older age
      • Renal failure
      • Certain HLA alleles
    • Clinical features
      • Fever
      • Pruritic morbilliform rash
      • Facial oedema
    • Multiorgan failure can occur
    • Fatal in 10%
    • Treatment
      • Drug cessation
      • Steroids
  • Toxic epidermal necrolysis (TEN) and Stevens-Johnson syndrome (SJS)
    • If < 10% of skin surface is involved -> SJS
    • If 10 – 30% of skin surface is involved -> SJS/TEN overlap
    • If > 30% of skin surface is involved -> TEN
    • Drugs
      • Antibiotics
      • Antiepileptics
      • Sulpha drugs
      • Allopurinol
    • Risk factors
      • HIV infection
    • Clinical features
      • High fever
      • Painful erythematous macules
      • -> Lesions form bullae
      • -> Extensive, full-thickness epidermal necrosis and sloughing
      • Resembles superficial burns
      • Mucous membranes almost always involved
        • Stomatitis
        • Oral ulcers
        • Conjunctivitis
        • Urethritis
      • Circulatory shock
    • Diagnosis
      • Clinical
      • Positive Nikolsky sign
    • Treatment
      • Supportive care
      • Drug cessation
      • High-dose steroid
      • IV immunoglobulin
      • GM-CSF
    • Mortality 10 – 50%
  • Acute generalized exanthematous pustulosis (AGEP)
    • Drugs
      • Penicillins
      • Quinolones
      • Sulpha drugs
    • Clinical features
      • Erythematous, oedematous pustules
      • Begin in intertriginous areas, progress over the whole body
      • Fever
    • Treatment
      • Drug cessation
      • Antipyretics
      • Oral steroids

15. Urticaria

  • Also called hives
  • Etiology
    • Basically anything, but often idiopathic
    • Physical urticaria
      • Most common
      • Pressure
      • Dermatographic urticaria
      • Elevated/decreased body temperature
      • Sweating
      • Sun-exposure
    • Allergic urticaria
      • Foods
        • Fish
        • Shellfish
        • Nuts
        • Eggs
      • Drugs
        • Penicillin
        • Aspirin
        • ACE inhibitors
        • NSAIDs
      • Inhalants
    • Autoimmune urticaria
    • Vasculitic urticaria
    • Infectious urticaria
    • Others
      • Insect bites/stings
      • Pregnancy
      • Exercise
      • Additives to food, dermatological products, soaps, etc.
  • Classification
    • Acute < 6 weeks
      • 95% of acute cases resolve
      • 5% progress into chronic
    • Chronic > 6 weeks
      • 25% of all urticaria patient
      • Etiology can’t be established in many cases
  • Pathomechanism
    • Local capillary vasodilation and transudation of fluid -> intradermal oedema
    • Mostly due to histamine, bradykinin, complement factors
    • Mast cell degranulation occurs
      • In some cases, due to hypersensitivity type I
  • Clinical features
    • Pruritus
    • Diffuse urtica/wheals
      • Circumscribed, sharply demarcated
      • Erythematous plaques, sometimes with central clearing
      • Individual lesions disappear after 24 hours
    • Angioedema may also occur
  • Diagnosis
    • Extensive history is essential
      • Any new dermatological products, drugs, etc.
    • Lab tests
      • Inflammatory markers
      • Autoantibodies
      • Infections
    • Prick test
    • Patch test
  • Treatment
    • For chronic
    • Oral antihistamines
    • Cyclosporine
    • Leukotriene antagonist
    • Omalizumab (anti-IgE)

16. Scabies, pediculosis

  • Scabies
    • Sarcoptes scabiei var hominis
      • Obligate human parasite
    • Transmission by direct physical contact or contact with infected clothes
    • Highly contagious
    • Incubation period 3 – 6 weeks
    • Risk factors
      • Nursing homes
      • Childcare facilities
      • Prisons
    • Pathomechanism
      • Female mites burrow into stratum corneum, lays eggs and feces
      • Feces and dead mites trigger type IV hypersensitivity
    • Clinical features
      • Intense pruritus, especially at night
      • Skin lesions
        • Elongated erythematous papules
        • 2 – 10 mm burrows (elevations in the skin)
        • Vesicles
        • Excoriation due to itching
      • Predilection sites – warm areas with thin skin
        • Wrists
        • Fingers
        • Male genitalia
    • Diagnosis
      • Dermoscope
      • Clinical
    • Treatment
      • Permethrin 5% lotion
        • Applied to the whole body and left on the skin for 8 – 12 hours
        • The rest of the family should be treated too
      • Lindane 1% lotion
      • Oral ivermectin
      • Symptomatic treatment of pruritus
        • Oral antihistamines
        • Topical steroids
  • Pediculosis
    • Lice infection
    • Transmission by direct physical contact or indirect contact with infected clothes, etc.
    • Risk factors
      • Crowded places
      • School
      • Homeless
    • Pathomechanism
      • Delayed allergic reaction to lice saliva
      • May be asymptomatic for weeks while sensitization occurs
    • Pediculosis capitis
      • Pediculus humanus capitis (head louse)
      • Most common in children
      • Clinical features
        • Scalp/neck pruritus
        • Louse eczema on back of neck
      • Diagnosis
        • Detection of lice on the scalp or hair
      • Treatment
        • Permethrin shampoo
        • Lindane shampoo
        • Malathion shampoo
        • Then mechanical removal with a fine-toothed comb
        • Cleaning of all hair tools, bedding, clothes, etc.
    • Pediculosis corporis
      • Pediculus humanus corporis (body louse)
      • Most common in crowded, unsanitary living conditions
      • Clinical features
        • Pruritus
        • Bites on skin
        • Scratching lines
      • Diagnosis
        • Detection of lice in clothing
      • Treatment
        • Topical permethrin
        • Cleaning of all bedding, clothes, etc.
    • Pediculosis pubis
      • Pthirus pubis (crab louse)
      • Transmitted by sexual contact
      • Most common in teenagers and young adults
      • Pruritus in genital area
      • Blue-purple macules in patients with chronic infection
      • Diagnosis
        • Detection of lice in pubic hair
      • Treatment
        • Topical permethrin
        • Cleaning of all bedding, clothes, etc.

17. Pigmented nevi

  • A nevus is a benign lesion of melanocytes in the skin or oral mucosa
  • Can be pigmented or non-pigmented (most are pigmented)
  • Histological classification
    • Junctional nevi
      • Flat, well-demarcated brown macules
      • Grows at the dermal-epidermal junction
    • Compound nevi
      • Elevated
    • Dermal nevi
      • Elevated
      • May be hard and grow hair
  • Clinical classification
    • Congenital
      • Small (< 1,5 cm)
      • Medium
      • Giant (> 20 cm)
    • Acquired
      • Common acquired nevus
        • < 6 mm
        • Symmetric
        • Homogenous surface
        • Even pigmentation
        • Round or oval shape
        • Sharply demarcated border
      • Atypical/dysplastic nevus
        • Share some similarities to melanoma
        • Must be differentiated from melanoma
        • Fried egg or target-shaped
        • May evolve
        • Atypical colour
        • Irregular, poorly demarcated
      • Spitz nevus
        • Not brown, rather pink, tan, red, etc.
        • In children
      • Halo nevus
        • Nevus surrounded by halo of depigmentation
      • Reed nevus
        • Very dark
        • On limbs
      • Nevus spilus
        • Tan macule speckled with smaller, darker macules
      • Blue nevus
  • Dysplastic nevus syndrome
    • Also called familial atypical multiple mole and melanoma syndrome (FAMMM)
    • High number (> 50) of common and atypical nevi and family history of melanoma
    • Almost 100% of developing melanoma
  • Diagnosis
    • History
      • Family history?
      • History of skin lesions?
      • History of sunburns?
      • When did nevus appear?
      • Has it changed?
    • Physical examination
      • Assess skin type
      • Examination with dermoscope
      • ABCDE
      • Ugly duckling sign

18. Vasculitides

  • Cutaneous small vessel vasculitis = cutaneous leukocytoclastic vasculitis
    • Small vessel vasculitides with cutaneous involvement
    • Most cases are idiopathic
    • Types
      • Immune complex mediated vasculitides
        • Cryoglobulinaemic vasculitis
        • IgA vasculitis = Henoch Schönlein purpura
        • Urticarial vasculitis
      • ANCA-associated vasculitides
        • Granulomatosis with polyangiitis
        • Eosinophilic granulomatosis with polyangiitis
    • Common clinical features
      • Palpable purpuras
      • Erythematous papules
      • Urticaria
      • Systemic symptoms
        • Fever
        • Myalgia
        • Arthralgia
        • Renal disease
    • Prognosis
      • 90% spontaneously resolve within months
      • 10% become chronic or recurrent
  • Cryoglobulinaemic vasculitis
    • Cryoglobulins = immunoglobulins that precipitate in the cold
      • They precipitate within the walls of small vessels
    • Etiology
      • Viral infections
      • Autoimmune connective tissue diseases
      • Haematological malignancies
    • Clinical features
      • Palpable purpura (in 90%)
      • Myalgia
      • Arthralgia
      • Peripheral neuropathy
      • Glomerulonephritis
    • Diagnosis
      • Examination of cryoglobulins in blood during attack
    • Treatment
      • Treat underlying disease
      • If severe
        • Steroids
        • Immunosuppressants
        • Biological therapy
  • IgA vasculitis = Henoch-Schönlein purpura
    • IgA deposit in the vessels
    • Typically affect children after a respiratory tract infection
    • Clinical features (typical tetrad)
      • Palpable purpura (in 100%)
      • Arthritis
      • Abdominal pain
      • Haematuria
    • Treatment
      • Self-limiting in most cases – no treatment needed
      • NSAIDs
      • Steroids if severe
  • Urticarial vasculitis
    • Persistent urticaria
    • Associated with autoimmune connective tissue diseases
    • Can be due to hypocomplementemia (deficiency of complement factors)
      • In which case there is also systemic involvement
    • Clinical features
      • Recurrent episodes of painful, persistent urticarial lesions that last > 24 hours
      • Angioedema can occur
    • Treatment
      • Antihistamines
      • Steroids
      • NSAIDs
      • Dapsone
  • Granulomatosis with polyangiitis
    • Potentially lethal
    • Clinical features
      • Skin symptoms (in 50%)
        • Papules
        • Purpuras
        • Oral ulcers
      • Chronic rhinosinusitis
      • Lower respiratory tract infections
      • Glomerulonephritis
    • Treatment
      • Steroids
      • Immunosuppressants
  • Eosinophilic granulomatosis with polyangiitis
    • Clinical features
      • Skin symptoms (in 50%)
        • Nodules
        • Palpable purpuras
      • Severe asthma
      • Allergic rhinitis
      • Respiratory tract infections
    • Treatment
      • Steroids
      • Immunosuppressants
  • Polyarteritis nodosa
    • Medium-sized vessel vasculitis
    • Clinical features
      • Skin symptoms (in 25%)
        • Palpable purpuras
        • Punched-out ulcers
      • Coronary artery disease
      • Renal disease
      • Polyneuropathy
    • Treatment
      • Steroids
      • Immunosuppressants

19. Contact dermatitis

  • Contact dermatitis
    • Types
      • Important types
        • Allergic contact dermatitis
        • Irritant contact dermatitis
        • Phototoxic contact dermatitis
        • Photoallergic contact dermatitis
      • Not so important types
        • Seborrheic dermatitis
        • Infectallergic dermatitis
        • Perioral dermatitis
        • Stasis dermatitis
    • Clinical features (rash)
      • Acute
        • “Sunburn type”
          • Erythema
          • Oedema
          • Vesicles
          • Urtica
          • Pruritus
        • “Exanthema type”
          • Macule
          • Papule
          • Plaque
          • Wheal
      • Subacute
        • Erythema
        • Fissure
        • Scaling
      • Chronic
        • Hyperkeratosis
        • Fissure
        • Scaling
        • Lichenification
    • Diagnosis
      • Patch test
        • Contains haptens in patches which are applied to the back
        • Reading at 48, 72, 168 hours
        • Contains common haptens according to European and local standards
          • Cosmetic ingredients
          • Plants
          • Metals
          • etc.
        • + = erythema, oedema
        • ++ = papule, vesicle
        • +++ = bulla, erosion, ulcer
        • Crescendo – reaction worsens with time
          • Typical for allergic contact dermatitis
        • Decrescendo – reaction improves with time
          • Typical for irritant contact dermatiti
    • Treatment
      • Identification of cause
      • Topical
        • Emollients (moisturizers)
        • Corticosteroids
        • Calcineurin inhibitors
      • Systemic
        • Antihistamines
        • Corticosteroids
  • Allergic contact dermatitis
    • Etiology
      • Poison ivy
      • Nickel
      • Chromium
      • Perfumes
      • Soaps
      • Cosmetics
      • Tattoos
      • Latex
      • Rubber
      • Topical medications
        • Budesonid
    • Pathomechanism
      • Type IVa hypersensitivity
      • Mediated by a hapten, which binds to an endogenous protein and becomes an immunogenic allergen
      • The body is sensitized to the allergen upon first contact
      • With repeated contact a rash develops
  • Irritant contact dermatitis
    • Etiology
      • Solvents – remove lipids in the stratum corneum
        • Like alcohol
      • Acids, bases, salts – destroy proteins in the stratum corneum
      • Dust – mechanically destroys stratum corneum
      • Excessive hand washing
      • Mineral oils
      • Detergents
      • Metals
      • Dry air
      • Warm air
      • Cold air
    • Pathomechanism
      • Not immune-mediated
      • Due to direct irritation -> leads to damage of stratum corneum
      • -> release of inflammatory mediators
  • Phototoxic contact dermatitis
    • More common than photoallergic type
    • Etiology
      • Topical
        • Bergamot
        • Psoralen (in plants)
        • Tar
      • Systemic
        • Tetracycline
        • Sulphonamides
        • Quinolones
        • HCTZ
    • Pathomechanism
      • UV radiation converts a photosensitive molecule into a cytotoxic one
    • Only occurs on sun-exposed skin
    • Phototoxic contact dermatitis is exploited in psoralen-UVA (PUVA) treatment
  • Photoallergic contact dermatitis
    • Less common than phototoxic type
    • Etiology
      • PABA
      • Perfumes
      • Aromatic oils
      • Benzocaine
    • Pathomechanism
      • UV radiation converts a photosensitive molecule (a photoallergen) into an allergen -> type IV hypersensitivity
    • Only occurs on sun-exposed skin

20. Precancerous lesions and intraepidermal carcinoma

  • Precancerous lesions
    • Lentigo maligna
    • Actinic keratosis
      • Cutaneous horns
    • Leucoplakia
  • Intraepidermal carcinoma/carcinoma in situ
    • Bowen disease
    • Erythroplasia of Queyrat
    • Paget disease
  • Lentigo maligna
    • Precancerous lesion of dysplastic melanocytes
    • Occurs in elderly
    • Risk factor: UV exposure
    • Darkly pigmented macule
      • On sun-exposed areas
        • Face, neck
      • Irregular borders
      • 1 mm – 2 cm
      • Irregular colour
    • Treatment
      • Surgical excision with safety margin
  • Actinic keratosis
    • Precancerous lesions of squamous cells
    • Occurs in elderly with light skin
    • Risk factor: UV exposure
    • Clinical features
      • Small lesion with rough surface
      • -> lesion grows and becomes erythematous and scaly
      • On sun-exposed areas
      • May develop into a cutaneous horn
    • Treatment
      • Few lesions
        • Cryotherapy
      • Many lesions
        • 5-FU
        • Imiquimod
      • Prevention with sunscreen
  • Leucoplakia
    • Hyperkeratosis and dysplasia of epithelium and mucous membranes
    • Risk factors
      • Smoking
      • Alcohol
    • Clinical features
      • White plaque that cannot be scraped off
      • Most commonly in oral cavity
    • Differential diagnosis
      • Oral candidiasis
      • Oral hairy leukoplakia
    • Treatment
      • Avoidance of risk factors
      • Cryotherapy
  • Bowen disease
    • Squamous cell carcinoma in situ of skin
    • Risk factors
      • UV exposure
      • HPV 16, 18
      • Arsenic
    • Clinical features
      • Erythematous and scaly lesion
      • Irregular shape, sharp borders
      • On sun-exposed areas
    • Treatment
      • 5-FU
      • Imiquimod
  • Erythroplasia of Queyrat
    • = Bowen disease of glans penis
    • Squamous cell carcinoma in situ of penile mucosa
    • Risk factors
      • Chronic inflammation
      • HPV 16, 18
    • Clinical features
      • Sharply demarcated, non-healing plaques or papules
      • May ulcerate or bleed
    • Treatment
      • 5-FU
      • Imiquimod
  • Paget disease of the breast
    • Ductal carcinoma in situ of the nipple and areola
    • Clinical features
      • Erythematous, scaly, vesicular rash
      • Pruritus
      • Burning
    • Treatment
      • Surgical removal

21. Cutaneous and mucosal manifestations and treatment of syphilis

  • Sometimes called lues
  • Treponema pallidum
  • Risk factors
    • Men who have sex with men
    • Promiscuity
    • Unprotected sex
  • Incubation period 10 – 90 days (average 21)
  • Has 4 characteristic stages
    • Primary syphilis
      • Characterised by a special lesion called a chancre
      • Chancres occur at the site where the bacterium enters the body
      • It’s a painless, firm ulcer with indurated borders and a smooth base
      • Chancres resolve spontaneously without scarring after 3 – 6 weeks
    • Secondary syphilis
      • Known as the “great imitator” as its skin symptoms resemble those of many other skin diseases
      • Both systemic and mucocutaneous lesions
      • Begins 8 – 12 weeks after primary infection
      • Lasts 2 – 6 weeks
      • Disseminated, symmetric rash
        • Polymorphic, i.e. can take on many appearances
        • Typically nonpruritic macular or papular rash
        • Reddish-brown
        • Roseola syphilitica = macules on trunk and flexor aspects of the extremities
        • Corona veneris
          • Maculopapular lesions
          • On forehead or back of neck
        • Clavus syphiliticus = maculopapular lesions on palms and soles
      • Mucous patches
        • White patches on mucous membranes
      • Condyloma lata
        • Broad-based, wart-like papular erosions
        • In anogenital region, intertriginous folds, oral mucosa
      • Patchy alopecia
      • Leucoderma syphiliticum
        • Hypopigmentation
        • Necklace of Venus = hypopigmentation around the neck
        • Differential diagnosis: pityriasis versicolor
      • Non-cutaneous and non-mucosal symptoms
        • Pharyngitis
        • Iritis
        • Hepatitis
        • Generalized nontender lymphadenopathy
        • Meningitis
    • Latent syphilis
      • The patient is seropositive but there are no symptoms
      • Can last months, years or the rest of the patient’s life
      • There are four outcomes
        • The disease resolves and the patient becomes healthy
        • The disease reactivates as secondary syphilis
        • The disease progresses into tertiary syphilis
        • The patient dies before any of these outcomes occur
    • Tertiary syphilis
      • Occur in approx. 30% of untreated patients in the latent stage
      • Late benign syphilis
        • Gummas
          • Destructive and ulcerative granulomatous lesions with necrotic centre
          • Can occur anywhere on or in the body, even on organs and bones
        • Nodules
        • Psoriasiform granulomatous lesions
      • Cardiovascular syphilis
        • Aortitis with resulting aneurysm of the aorta
        • Dilated aortic root
      • Neurosyphilis
        • Early neurosyphilis
          • Meningitis
          • Stroke
        • Late neurosyphilis
          • Tabes dorsalis

Demyelination of the dorsal column and dorsal root ganglia

Causes a broad-based ataxia

          • Dysesthesia

Abnormal peripheral sensation

          • General paresis

Widespread cerebral atrophy

Dementia

          • Argyll Robertson pupil

Bilateral miosis

Pupils don’t react to light

  • Diagnosis
    • Direct visualization of treponema
      • In the primary stage, when the serological tests below can be negative
      • Darkfield microscopy
      • Specimen from a lesion
    • Nontreponemal tests – for screening
      • RPR
      • VDRL
      • Sensitive, not specific
    • Treponemal test – for confirming the diagnosis
      • TPPA
      • FTA-ABS
      • Specific, not sensitive
  • Treatment
    • For prevention, primary, secondary and early latent syphilis
      • 2,4 million units of benzathine penicillin G intramuscularly – single dose
    • For tertiary (except neurosyphilis) and late latent syphilis
      • 2,4 million units of benzathine penicillin G IM – once weekly for three weeks
    • For neurosyphilis
      • IV penicillin G for 10 to 14 days
    • Jarisch-Herxheimer reaction may occur
      • Systemic reaction to bacterial endotoxins
      • Is usually self-limiting
    • In case of penicillin allergy
      • Doxycycline
      • Desensitization to penicillin, then use penicillin as normal

22. Diagnosis and treatment of gonorrhoea

  • Epidemiology
    • Young adults
  • Neisseria gonorrhoeae
  • Clinical features in men
    • Incubation time – 2 to 10 days
    • 15% are asymptomatic
    • Acute gonococcal urethritis
      • Discomfort
      • Dysuria
      • Purulent discharge
    • Chronic gonococcal urethritis
    • Complications
      • Epididymitis
      • Seminal vesiculitis
      • Prostatitis
  • Clinical features in women
    • Incubation time – days to weeks
    • 30 – 60% are asymptomatic
    • Acute salpingitis
    • Dysuria
    • Increased discharge
    • Abnormal bleeding
    • Complications
      • Pelvic inflammatory disease
  • Disseminated gonococcal infection (arthritis-dermatitis syndrome)
    • Occurs in 2% of cases
    • 85% are women
    • Intermittent fever
    • Migratory arthritis
      • Pain spreads from one joint to another
    • Skin lesions
      • Flea bite-like papules
      • Haemorrhagic pustules on palms, soles
  • Gonococcal conjunctivitis (in neonates)
    • Etiology
      • Direct contact from genitalia to hand to eye
      • Perinatally
    • Treatment
      • Silver nitrate eye drops
  • Diagnosis
    • PCR (a type of NAAT)
      • First choice
      • Of first urine – in men
      • Of vaginal swab – in women
      • Of pharyngeal swab – if oral sex occurred
    • Gram staining
    • Culture
  • Treatment
    • Ideal treatment for gonorrhoea:
      • Treats the gonorrhoea
      • Treats and any coexisting syphilis and chlamydia
      • Is single dose
      • Covers resistant strains of gonorrhoea (many are resistant to cephalosporins)
    • Either
      • Single-dose ceftriaxone IM + single-dose azithromycin PO
      • or single-dose cefixime PO + single-dose ciprofloxacin PO
    • Postgonococcal urethritis can occur
      • Due to secondary colonization with mycoplasma and chlamydia
      • Treatment: tetracycline

23. Acne and its treatment

  • Common acne = Acne vulgaris
  • (comedo/comedones = plugged hair follicle (pore))
  • Risk factors
    • Genetic predisposition
    • Hormonal changes
      • Puberty
      • Menstrual cycle
    • Certain foods
    • Smoking
    • Skin products that block pores
  • Pathomechanism
    • Hyperactivity of sebaceous glands
    • Hyperkeratosis of follicular keratinocytes
    • Bacterial hypercolonization
      • Propionibacterium acnes (= cutibacterium acnes)
    • Inflammation
  • Clinical features
    • On face, shoulders, upper chest, back
    • Primary lesions
      • Non-inflammatory acne – comedonal acne
        • Closed comedones = whiteheads
          • Small papules that contain whitish material
          • The whitish material is keratin and sebum
        • Open comedones = blackheads
          • Small papules with black material
          • The black material is oxidized keratin and sebum
      • Inflammatory acne
        • Papular acne
        • Pustular acne
        • Nodular acne (> 5 mm)
    • Secondary lesions
      • Erythema
      • Hyperpigmentation
      • Scarring
        • Hypertrophic scars
        • Depressed scars
        • Pitted scars
  • Special types of acne
    • Acne inversa = hidradenitis suppurativa
      • Inflammation of hair follicles due to physical blockage by skin folds, etc
    • Acne fulminans
      • Sudden onset, very severe acne
      • In teenage boys
  • Diagnosis
    • Anamnesis
    • Clinical examination
    • Laboratory examinations
      • Exclude hyperandrogenism, like PCOS, CAH, androgen-producing tumors
  • Treatment
    • Options
      • Topical benzoyl peroxide
        • Comedolytic
        • Bactericidal
      • Retinoids
        • Oral or topical
        • Tretinoin, isotretinoin, adapalene
        • Normalize keratinocyte differentiation
        • Decrease sebum production
        • Highly teratogenic
          • Females must produce negative pregnancy test and use at least one, optimally two methods of contraception
        • Hepatotoxic
          • Liver enzymes, cholesterol must be monitored
      • Antibiotics
        • Oral (doxycycline, minocycline)
        • Topical (erythromycin, clindamycin)
        • Bactericidal
        • Decrease inflammation
      • Oral contraceptives
        • In females
        • Can be added in treatment failure
      • Topical combination therapy
        • Benzoyl peroxide + topical retinoid
        • Benzoyl peroxide + topical antibiotic
        • Benzoyl peroxide + topical retinoid + topical antibiotic
    • Treatment algorithm
      • Mild cases
        • Topical benzoyl peroxide
        • Topical retinoid
        • Topical combination therapy
      • Moderate cases
        • Topical combination therapy
        • Oral antibiotic + topical combination therapy
      • Severe cases
        • Oral retinoid

24. Local therapy in dermatology

  • Unilateral treatment allows for easier treatment response evaluation than with systemic treatment
  • Topical preparations/formulations consist of a drug in a non-active base/vehicle
  • Drugs used on skin must be dissolved or suspended in a vehicle
    • The choice of drug depends on the diagnosis
    • The choice of vehicle depends on the state of the skin
    • The drug will be transferred from the vehicle to stratum corneum
    • The base determines the rate at which the drug is absorbed through the skin
  • Vehicles
    • Liquid vehicles
      • Water
      • Ethanol
      • Glycerol
    • Solid vehicles (powders)
      • Zinc oxide
      • Titanium oxide
      • Talc
      • Starch
    • Fatty vehicles (greases)
      • Vegetable fats
      • Animal fats
      • Mineral oils
      • Petrolatum
  • Types of topical preparations

  • Topical preparations
    • Solution
      • Drug dissolved in a liquid solvent like alcohol or water
      • Convenient to apply (can be applied with a dropper)
    • Lotions
      • Water-based emulsion
      • Thicker than solution
      • Good for hairy skin
      • They cool inflammatory lesions and dry exudative lesions
    • Creams
      • A semisolid emulsion of water in oil or oil in water
      • Thicker than lotion
      • Good for weeping lesions
      • When applied with wet compress -> good for inflamed skin
    • Ointments
      • Semisolid grease or oil, without water
      • Good for scaly or dry lesions
      • When applied with wet compress -> good for inflamed skin
    • Gels
      • Soft, semisolid preparation
      • Liquefy on contact with the skin
    • Foam
      • Aerosolized solution with a pressurized propellant
      • Good for hairy skin
    • Powders
      • Solid
      • For lesions in moist or intertriginous areas
    • Cooling paste
      • Contains oil, water and powder
      • Often contains zinc oxide
      • Cools inflamed skin
  • Dressings
    • Protect open lesions, facilitate healing, increase drug absorption
    • Non-occlusive dressings (wet dressings)
      • Dressings wetted with saline or water
      • Applied to the lesion and removed when the solution has evaporated
      • Good for thick or crusted lesions
      • Good for oozing lesions
    • Occlusive dressings
      • Increase the absorption and effectiveness of topical therapy
      • Can be applied over topical preparations to increase absorption
      • Can be applied to open wounds to allow them to heal
  • Moisturizing agents (emollients)
    • Restore water and oil to skin and help maintain skin hydration
    • More effective in slightly wet skin, like after a shower
    • Available as lotions, creams, ointments, etc.
    • Indicated in dry skin conditions
    • Contains occlusives and humectants
    • Humectants
      • These agents attract water, increasing the water-holding capacity of the stratum corneum
      • Glycerine
      • Urea
      • Lactic acid
      • Glycolic acid
    • Occlusives
      • Form a physical barrier to prevent water loss
      • Waxes
      • Petrolatum
      • Oils
  • Drying agents (powders)
    • To treat excessive moisture, like between skin folds, the groin, etc
    • Corn starch
    • Talc
  • Topical agents to alleviate pruritus
    • Pramoxine
    • Hydrocortisone
    • Menthol
    • Phenol
  • Keratolytics
    • These agents facilitate exfoliation of epidermal cells
    • Used to treat hyperkeratotic diseases like
      • Psoriasis
      • Seborrheic dermatitis
      • Acne
    • Urea
    • Salicylic acid
    • Lactic acid
    • Glycolic acid
  • Steroids
    • Widely used in dermatology
    • Indications
      • Cutaneous lupus erythematosus
      • Psoriasis
      • Lichen
      • Contact dermatitis
      • Atopic dermatitis
      • Allergic skin reactions
    • Mostly used steroids
      • Hydrocortisone (low potency)
      • Triamcinolone (medium potency)
      • Clobetasol (high potency)
    • Side effects
      • Skin atrophy
      • “Steroid acne”
      • Striae
      • Contact allergy
      • “Steroid rosacea” = perioral dermatitis
        • When potent steroids are used on the face
        • Telangiectasias
        • Papules, pustules
  • Topical antibiotics
    • Mostly used in acne
    • Tetracyclines
    • Metronidazole
    • Erythromycin
    • Clindamycin
    • Bacitracin
  • Silver nitrate
    • Low concentration – debride wounds
    • High concentration – cauterizes bleedings in wounds
  • Imiquimod
    • Immune regulator
    • Indications
      • Warts
      • BCC
      • Actinic keratosis
  • Topical calcineurin inhibitors
    • Tacrolimus
    • Pimecrolimus
    • Indications
      • Atopic dermatitis
  • 5-fluorouracil
    • Indications
      • Actinic keratosis
      • BCC
      • Warts
  • Fingertip units (FTU)
    • 1 FTU = the amount of topical preparation expressed from a tube when applied from the distal skin-crease to the tip of the index finger
    • 1 FTU is approx. 0,5 g
    • 1 FTU covers approx. 300 cm2, which is enough for one hand
    • 2,5 FTU covers the face and neck
    • Fingertip units are useful when telling patients how much they should use of a preparation

B. topics

1. The structure of the skin and its function

  • 2 m2 and 4 kg
  • Structure
    • Epidermis
      • Stratum corneum
      • Stratum lucidum
      • Stratum granulosum
      • Stratum spinosum
      • Stratum basale
    • Dermo-epidermal junction
      • Basement membrane
    • Dermis
      • Papillary dermis
        • Loosely arranged collagen
        • Supplies epidermis with nutrients through dermal papillae
      • Reticular dermis
        • Densely packed reticular, elastic, collagen fibres
      • Connective tissue
      • Dense innervation
    • Subcutis/hypodermis
      • Fat
      • Connective tissue that anchors the skin to the deep fascia
  • Function
    • Mechanical, chemical, physical, microbial barrier
      • Desmosomes attach keratinocytes to each other
      • Hemidesmosomes attach keratinocytes to basement membrane
    • Protect against UV radiation
      • Melanocytes
    • Immune function
      • Skin associated lymphatic tissues (SALT)
      • Langerhans cells – tissue macrophages in stratum spinosum
      • Recruits the immune system when something crosses the barrier
    • Vitamin D synthesis
    • Sensory
      • Touch
        • Meissner corpuscles – fine touch
        • Ruffini corpuscles – pressure
      • Vibration
        • Pacinian corpuscles
      • Temperature and pain
        • Free nerve endings
    • Temperature regulation

2. Alopecias

  • Phases of hair growth
    • Anagen phase – hair growth
    • Catagen phase – transition phase
    • Telogen phase – resting phase
    • Repeat
  • Types of alopecia
    • Diffuse alopecia
      • Androgenetic alopecia
        • Most common cause
        • In androgen-sensitive hair follicles
          • Bitemporal scalp in men
          • Frontal scalp in women
        • Androgens shorten the anagen phase
      • Telogen effluvium
        • Endocrine disorders
        • Drugs
        • Malnutrition
        • Severe stress
    • Circumscribed alopecia
      • Alopecia areata
        • Autoimmune
        • Bacterial infection
        • Stress
      • Syphilitic alopecia
      • Scarring alopecia
        • Trauma
        • Burn
        • Ulcerating skin diseases
  • Treatment
    • Finasteride
    • Minoxidil
    • Hair transplant
    • PUVA
    • Imiquimod
    • Tacrolimus
    • etc.

3. Dermatomyositis

  • = inflammatory myopathy with skin involvement
  • In older adults
  • In children (juvenile dermatomyositis)
  • Etiology
    • Autoimmune
    • Associated with malignancies (in adults)
  • Clinical features
    • Muscle atrophy and weakness
    • Heliotrope rash
      • Erythematous/purple rash of periorbital area
    • Gottron papule
      • Erythematous papules on knuckles
    • Shawl erythema
      • Erythema of neck, upper trunk
  • Diagnosis
    • Creatine kinase
    • LDH
    • Autoantibodies
    • Muscle biopsy
  • Treatment
    • Steroids

4. Symptoms, diagnosis and treatment of non-gonorrhoeic urethritis

  • Epidemiology
    • Chlamydia is most common STD (except HPV)
  • Etiology
    • Chlamydia trachomatis D-K
    • Mycoplasma
    • Ureaplasma
    • Trichomonas
  • Clinical features in females
    • 90% are asymptomatic
    • Urethritis
    • Mucopurulent discharge
    • Postcoital bleeding
    • Extra in trichomonas
      • Yellow-greenish discharge
      • Abnormal vaginal odour
  • Clinical features in males
    • 50% are asymptomatic
    • Prostatitis
    • Epididymitis
  • Complication: Reiter syndrome/reactive arthritis
    • Most commonly after chlamydial urethritis
    • Associated with HLA-B27
    • Affects young males
    • Clinical triad
      • Arthritis
      • Conjunctivitis
      • Urethritis
  • Diagnosis
    • PCR of vaginal swab or first catch urine
      • Mycoplasma
      • Chlamydia
      • (also Gonorrhoea)
    • Whiff test – trichomoniasis
      • KOH added – fishy odour
      • Microscopy
  • Treatment
    • Chlamydia
      • Single dose 1g PO azithromycin
    • Trichomonas
      • Single dose 2g PO metronidazole
    • Others
      • Doxycycline
      • Azithromycin

5. Clinical forms and treatment of Kaposi sarcoma

  • Caused by HHV8
  • Malignant tumor of endothelial cells
  • 4 types
    • Classic – in older males
    • Endemic – in Africa
    • Immunosuppressive therapy-related
    • AIDS-related
  • Clinical features
    • Multiple cutaneous lesions
      • Purplish macules -> patches -> papules -> plaques -> nodules
    • Rapidly growing
    • Initially seen on face, oral cavity or chest
    • Organs can be involved
  • Treatment
    • Vinblastine
    • Radiotherapy
    • Treat underlying HIV

6. Lichen planus

  • Chronic inflammatory disease of unknown etiology
  • Associated with hep C
  • Cutaneous lichen planus
    • 5 P’s
      • Purple
      • Planar
      • Pruritic
      • Polygonal
      • Papules
    • Wickham striae – characteristic white lines
  • Mucosal lichen planus
    • Wickham striae in oral cavity
    • Painful, erosive lesions in oral cavity
    • Can also affect oesophagus
  • Genital lichen planus
    • Papules on genital organs
  • Treatment
    • Topical/oral steroids
    • Phototherapy

7. Clinical outcome and symptoms of AIDS

  • General cutaneous clinical features
    • Opportunistic infections
      • Oral/oesophageal candidiasis
      • Cryptococcus
      • Aspergillosis
      • Dermatophytes
    • Herpes simplex infections
    • Psoriasis
    • Herpes zoster
      • AIDS can cause reactivation
    • Molluscum contagiosum
    • Atopic dermatitis
    • Seborrheic dermatitis
    • Drug reactions
      • More severe in AIDS
      • Often cause morbilliform rash
  • Specific cutaneous clinical features
    • Acute HIV syndrome
      • Before AIDS develops
      • Maculopapular morbilliform rash
    • Eosinophilic folliculitis
      • Pruritic, erythematous papules on follicles
      • Affects the upper body only
    • Oral hairy leucoplakia
      • EBV
      • White plaques
      • On inferolateral surface of tongue
    • Bacillary angiomatosis
      • Bartonella
      • Multiple erythematous papules and nodules
      • Bleed easily
    • Kaposi sarcoma

8. Benign tumours of the skin

  • Epidermal origin
    • Seborrheic keratosis
      • Most common benign skin tumor in elderly
      • Immature keratinocytes
      • Clinical features
        • Multiple darkly pigmented, soft papules/plaques
        • Greasy, wax-like
        • “Stuck-on” appearance
        • May be pruritic
        • May bleed easily
        • Increase in number and size with time
      • Treatment
        • No treatment necessary
        • Cryotherapy, laser, excision for cosmetic reasons
    • Keratoacanthoma
      • On sun-exposed skin
      • From pilosebaceous glands
      • Rapid growths for a few weeks -> then spontaneous resolution after months
      • Treatment
        • Excision
        • Radiotherapy
    • Sebaceous nevus
    • Apocrine nevus
  • Benign mesenchymal tumors
    • Dermatofibroma
      • Fibroblasts
      • Slowly growing
      • Skin-coloured or brownish nodules
      • Most commonly on lower extremities
      • Fitzpatrick sign – when squeezed the surface retracts inwards
        • Characteristic for dermatofibroma
      • Treatment only for cosmetic reasons
    • Acrochordon (skin tag)
    • Lipoma
      • Slow growing
      • Round
      • Soft
      • “Rubbery”
    • Leiomyoma
  • Vascular tumors
    • Angioma
    • Haemangioma
    • Pyogenic granuloma
      • Benign vascular tumor
      • Soft, round, bright red tumor
      • Bleeds easily
  • Skin adnexal benign tumors – of accessory skin structures like glands, hair follicles
    • Syringoma
    • Hidradenoma
    • Trichoepithelioma
    • Dermal eccrine cylindroma
      • Solid, skin-coloured nodules
      • On head, neck, face
  • Other
    • Epidermoid cyst
    • Pigmented nevus
    • Neurofibroma
      • Neurofibromatosis

9. Paraneoplastic skin disorders

  • Indicate underlying malignancy
  • Occur due to tumor-associated immunological and endocrine mechanisms
    • Autoimmune reactions
    • Growth factor synthesis
    • etc.
  • Often therapy-resistant
  • Obligate paraneoplastic disorders
    • Leser-Trélat sign
      • Multiple, sudden-onset seborrheic keratoses
      • Solid cancers, especially GI tract
    • Malignant acanthosis nigricans
      • EGF production
      • Asymmetric velvety thickening and hyperpigmentation of skin folds
      • Pruritus
      • GI, lung cancers
    • Erythema gyratum repens
      • Adenocarcinoma
    • Acrodermatitis psoriasiformis
      • Upper airway cc
    • Hypertrichosis acquisita
    • Acrokeratosis bazex/acrokeratosis paraneoplastica
      • Psoriasiform lesions
      • Upper airway cc or GI cc
    • Paraneoplastic pemphigus
  • Facultative paraneoplastic disorders
    • Pyoderma gangrenosum
      • Painful, rapidly progressive ulcerated lesions
      • Also in Crohn’s
    • Bullous pemphigoid
    • Dermatomyositis
    • Sweet syndrome
      • Painful erythematous papules, plaques, nodules
    • Herpes zoster generalisatus
    • Acquired, generalized ichthyosis

10. Rosacea, rhinophyma

  • Rosacea
    • Chronic inflammatory skin disease
    • More common in females
    • Triggers
      • Alcohol
      • Stress
      • Smoking
      • Hot weather
    • Clinical features
      • No comedones or seborrhoea
      • Erythematotelangiectatic rosacea
        • Central facial erythema
        • Telangiectasia
      • Papulopustular rosacea
        • Papules, pustules and erythema
      • Phymatous rosacea
        • Skin thickens
        • Inflammatory nodules
        • Rhinophyma – large, bulbous nose
      • Ocular rosacea
        • Conjunctival hyperaemia
        • Blepharitis
        • Dry eyes
        • Keratitis
    • Treatment
      • Avoid triggers
      • Topical
        • Metronidazole
        • Ivermectin
        • Azelaic acid
      • Oral
        • Tetracycline
        • Metronidazole
        • Isotretinoin
      • Rhinophyma – surgical treatment

11. Tuberculosis of the skin and its treatment

  • Cutaneous tb is a rare form of extrapulmonary tb
  • Multiple types
    • Tuberculous chancre
      • Occurs at the site where m. tuberculosis enters the skin
      • In people who don’t already have TB
      • Papule -> painless ulcer
    • TB verrucosa cutis
      • Occurs at the site where m. tuberculosis enters the skin
      • In people who already have TB
      • Purplish warty growth
    • Lupus vulgaris
      • Apple-jelly nodules (gelatinous consistency)
      • Sharply defined reddish-brown lesions
      • On head
    • Scrofuloderma
      • Direct extension of underlying TB from lymph nodes, bones or joints to the skin
      • Firm, painless nodules -> ulcerate
    • Miliary TB
      • Haematogenous dissemination of m. tuberculosis
      • Small (millet-sized) erythematous papules -> ulcers, abscesses
    • Tuberculids
      • Papulonecrotic tuberculid
        • Necrotic papules
      • Erythema induratum
        • Hard nodules on back of legs of women
  • Diagnosis
    • Tuberculin skin test (TST) / purified protein derivative (PPD)
    • Interferon gamma release assay (IGRA)
  • Treatment
    • RIPE for 2 months
    • RI for 4 months

12. Photodermatoses and phototherapy

  • Photodermatoses – skin diseases that develop due to light exposure
  • Photodermatoses of unknown origin
    • Solar dermatitis = sunburn
      • UVB radiation causes apoptosis of keratinocytes -> release of inflammatory cytokines
      • Clinical features
        • Pruritus, pain
        • Erythema, oedema
        • Blisters (severe)
      • Treatment
        • Wet compress
        • Cooling ointments
        • Topical steroids
    • Polymorphous light eruption (PLE)
      • Chronic disease
      • In adult females
      • Most common photodermatitis
      • Clinical features
        • Itching, burning erythema
        • Malaise, headache
    • Solar urticaria
      • Rare
      • Type I hypersensitivity
      • Urtica at site of sun exposure
    • Actinic prurigo
    • Chronic actinic dermatitis
  • Photodermatoses of known origin
    • Phototoxic reactions
    • Photoallergic reactions
  • Diagnosis
    • Photo-patch test
      • UVA applied, then patch
      • Read immediately, then at 24, 48, 72 hours
    • Photo-provocation test
      • Differentiate between solar urticaria, chronic actinic dermatitis, polymorphous light eruption, SLE
  • Treatment
    • Photohardening
    • Photoprotection
  • Phototherapy
    • Indications
      • Psoriasis
      • Atopic dermatitis
      • Alopecia areata
      • Granuloma annulare
      • Cutaneous T-cell lymphoma
      • Vitilligo
      • Photodermatoses
      • BCC
      • Actinic keratosis
    • Mechanisms
      • Thickens epidermis
      • Hyperpigmentation
      • Immunosuppressive effect
      • Anti-tumor effect
    • Procedure
      • Minimal erythematous dose (MED) is determined
      • The dose of UV light depends on the MED
    • Types
      • Narrow-band UVB
      • Broad-band UVB
      • Selective UVB
      • Psoralen + UVA
      • Photodynamic therapy
        • Uses visible light, not UV
        • For cancers that are caused by UV (BCC)

13. Lyme Borreliosis

  • Tick-borne
  • Borrelia burgdorferi
  • Clinical features
    • Stage I – early localized Lyme disease
      • Within 7 – 14 days
      • Erythema migrans
        • Circular, slowly-expanding red ring with central clearing around the bite site
        • Target-like rash
      • Flu-like symptoms
    • Stage II – early disseminated Lyme disease
      • Multiple erythema migrans
      • Migratory arthralgia
      • Early neuroborreliosis
      • Lyme carditis
    • Stage III – late Lyme disease
      • Acrodermatitis chronica atrophicans
        • Inflammation and atrophy of skin of extremities
      • Chronic Lyme arthritis
      • Late neuroborreliosis
  • Diagnosis – serology
  • Treatment
    • Doxycycline
      • First-line
    • Amoxicillin
      • In pregnant
    • Ceftriaxone
      • If neuroborreliosis or Lyme carditis

14. Types of allergic skin reactions

  • Type I hypersensitivity
    • Skin reactions
      • Angioedema
      • Urticaria
    • Diagnosis – prick test
    • Treatment
      • Antihistamines
      • Epinephrine
  • Type II hypersensitivity
    • Not important
  • Type III hypersensitivity – immune complex-mediated
    • Cutaneous vasculitis
    • Serum sickness
    • Treatment
      • Steroids
  • Type IV hypersensitivity
    • Type IVa – Allergic contact dermatitis
    • Type IVb – Drug-related eosinophilia and systemic symptoms (DRESS)
    • Type IVc – Toxic epidermal necrolysis/Stevens-Johnson syndrome
    • Type IVd – Acute generalized exanthematous pustulosis (AGEP)
    • Diagnosis – patch test
    • Treatment
      • Steroids

15. Cutaneous manifestation of diabetes mellitus

  • 30% of all diabetes patients will experience skin symptoms
  • Non-specific skin conditions
    • Impetigo
    • Candida intertrigo
    • Psoriasis
    • Necrotizing fasciitis
    • Acanthosis nigricans
  • Specific skin conditions
    • Diabetic dermopathy
      • Reddish, oval/round scaly patches
      • Often on the shins
    • Diabetic bullae
      • Painless bullae
      • Can be very large
      • Intraepidermal bullae
        • More common
        • Filled with clear fluid
        • Heal without scarring or atrophy
      • Subepidermal bullae
        • Less common
        • Filled with blood
        • Heal with scarring and atrophy
    • Diabetic sclerosis
      • In diabetes type 1
      • Sclerosis of finger skin -> restricted mobility
    • Foot ulcers (diabetic foot)
    • Necrobiosis lipoidica diabeticorum
      • Erythematous patches on lower legs
      • May ulcerate and become infected

16. Primary skin lesions, basics of dermatohistopathology

  • Primary skin lesions
    • Flat lesions
      • Macule
        • A flat skin lesion < 1 cm in size with discolouration
      • Patch
        • A flat skin lesion > 1 cm in size with discolouration
    • Infiltrative lesions
      • Papule
        • An elevated palpable skin lesion < 0,5 cm in size
        • Epidermal
      • Plaque
        • An elevated palpable skin lesion > 0,5 cm in size
        • Intradermal
      • Tuber
        • An elevated palpable skin lesion whose infiltration involves the entire depth of the dermis
      • Nodule
        • A circumscribed elevated lesion > 1 cm
        • In dermis and subcutis
      • Tumor
        • Large solid mass of tissue
    • Fluid-filled lesions
      • Vesicle
        • Small fluid-containing lesion
        • Intraepidermal
      • Bulla
        • Large fluid-containing lesion
        • Intraepidermal or subepidermal
      • Urtica/wheal
        • Transient oedema in the dermis
      • Pustule
        • Collection of pus in or below the epidermis
  • Dermatopathological terms
    • Acantholysis
      • Separation of epidermal cells due to dissolution of desmosomes
      • E. g. in pemphigus vulgaris
    • Acanthosis
      • Hyperplasia of stratum spinosum
      • E.g. in acanthosis nigricans
    • Hypergranulosis
      • Hyperplasia of stratum granulosum
      • E.g. in lichen planus
    • Hyperkeratosis
      • Hyperplasia of stratum corneum
      • E.g. in psoriasis
    • Papillomatosis
      • Hyperplasia and enlargement of dermal papillae
    • Parakeratosis
      • Keratinocytes in stratum corneum retain their nuclei
      • E.g. in
        • Psoriasis
        • Dandruff
    • Spongiosis
      • Intraepidermal oedema
      • E.g. in
        • Atopic dermatitis
        • Allergic contact dermatitis

17. Secondary skin lesions, basics of dermatohistopathology

  • Secondary skin lesions
    • Scales
      • Detaching fragments of a thickened stratum corneum
      • Dry and usually whitish
    • Erosion
      • Loss of epidermis
      • Heal without scarring
    • Excoriation
      • Loss of papillary dermis
      • Heals with scarring
    • Fissure
      • Painful, deep, linear opening of skin through the epidermis and into the dermis
    • Rhagades
      • Cracks or tears in the skin caused by stretching of brittle skin
    • Ulcer
      • Skin defect with loss of epidermis and upper papillary dermis
      • Usually leave scars
    • Crust
      • Dried secretion
      • Red-brown crust – blood
      • Yellow crust – serum
      • Honey-coloured crust – purulent streptococcus exudate
      • Yellow-green crust – purulent staphylococcus exudate
    • Scar
      • Permanent fibrous lesions
      • A result of the repair process
      • Hypertrophic scar = keloid scar
      • Atrophic scar
    • Atrophy
      • Thinning of epidermis and dermis
    • Lichenification
      • Increased thickness of epidermis
      • Cobblestone-like surface
      • A result of chronic rubbing or scratching

18. Cutaneous T-cell lymphomas

  • Mycosis fungoides
    • CD4+ T-cell lymphoma
    • Progresses slowly
    • Stage I – patch stage
      • Scaly, pruritic, well-demarcated patches
    • Stage II – plaque stage
      • Scaly, pruritic, well-demarcated plaques
      • Large
    • Stage III – tumor stage
      • Dome-shaped purple or red nodules
    • Treatment
      • Topical steroids
      • Topical chemo
      • Phototherapy
      • Biological therapy
      • Systemic chemo
  • Sézary syndrome
    • Can develop from mycosis fungoides or de novo
    • Clinical triad
      • Systemic skin lesions
        • Erythroderma
        • Palmar and plantar hyperkeratosis
        • Pruritus
      • Generalized lymphadenopathy
      • Atypical T-cells in blood
    • Treatment
      • Extracorporal photopheresis
      • Phototherapy
      • Chemotherapy
  • Adult cutaneous T-cell leukaemia/lymphoma
    • HTLV-I associated
    • Similar lesions to mycosis fungoides

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